This assumes you have installed Docker on Linux and Docker is running. 

Let's say you've created a network named my-network and that you've created a container named my-container. The docker inspect command can be used to determine the network(s) the container is using.

docker inspect my-container

In this example, my-container is using one network (bridge).

"Networks": {
  "bridge": {

The docker network connect command can be used to connect a docker container to another docker network. In this example, my-container is connected to my-network.

docker network connect my-network my-container

Reissuing the docker inspect command should now show that my-container is connected to bridge and my-network.

"Networks": {
  "bridge": {
  . . .
  "my-network": {

The docker network disconnect command can be used to disconnect a docker container from a docker network. In this example, my-container is disconnected from bridge.

docker network disconnect bridge my-container

Reissuing the docker inspect command should now show that my-container is connected to only my-network.

"Networks": {
  "my-network": {